Our research efforts
In our goal to advance electrochemical science and engineering, we perform fundamental research in these three disciplines:
Emerging applications require materials with sophisticated control over the 3D architecture at different length-scales. For example, engineering an adequate average pore size distribution, porosity, and tortuosity would reduce pressure drop losses, improve mass transport and reaction distribution, decrease ohmic resistance, and maintain a low weight. In this program, we design, simulate, and manufacturing architected porous electrodes with various degrees of hierarchical organization. Examples of ongoing projects include:
- Simulating electrochemical phenomena within porous electrodes with pore network modeling. Developing predictive modeling frameworks based on evolutionary algorithms and 3D simulations.
- 3D printing of electrodes and flow fields to elucidate structure-performance relationships.
- Developing versatile and scalable synthetic platforms (e.g. phase separation, hydrogen bubble templating) to conventional fiber-based electrodes.
The interfacial properties of solids and the interacting fluid define a number of important characteristics, such as electrochemically-active surface area, intrinsic activity, stability, and selectivity. In this program, we employ electrografting and other techniques to grow thin films of selected polymers with tailored properties onto the surface of model electrodes and porous materials. Examples of ongoing projects in this space include:
- Developing kinetically active and selective electrode interfaces for flow batteries.
- Engineering thin-film ionomers for fuel cells and electrolyzers.
- Developing porous electrode interfaces with precisely controlled wettability.
Traditional electrochemical diagnostics are based on measuring the voltage response to an applied current (or vice versa). However, our ability to deconvolute the underlying thermodynamic, kinetic, and transport processes is still quite limited – it remains a black box. In this program, we are interested in understanding the performance of materials during operation through visualization of local properties (i.e. concentration, flow distribution, temperature). Pursuant to this goal, we employ advanced imaging techniques, namely neutron imaging and X-ray tomographic microscopy, tin combination with electrochemical diagnostics. Examples of ongoing projects include:
- Neutron imaging of electrochemical systems to visualize local concentrations.
- X-ray tomographic microscopy to visualize the electrode 3D structure.
- Electrochemical diagnostics to assess the full device performance.
The technologies we develop
We apply these fundamental principles to advance three emerging technologies:
Redox flow batteries are a promising platform technology for grid-scale and long-duration energy storage due to their ability to decouple energy and power, facile manufacturing, and intrinsic safety. However, current flow battery designs are not cost competitive, which motivates research into novel reactor architectures and materials. In this area, we work on the following topics: :
- Engineering porous electrodes for aqueous and non-aqueous redox flow batteries.
- Designing electrochemical reactor concepts for high power density flow cells.
- Understanding degradation pathways in redox flow batteries.
- Investigating ultralow cost battery systems (e.g. metal-air flow batteries).
Polymer electrolyte membrane fuel cells represent a promising electrochemical technology for stationary and transportation applications as they provide pollution-free, high-power, and fast-refilling means of interconverting chemical and electrical energy. However, widespread commercialization is currently hampered by elevated costs. Increasing device power density and durability, which necessitates the development of a new class of porous materials with optimized properties, is a key strategy to lower the costs. In this area, we work on the following topics:
- Developing new ionomers with improved mass transport.
- Synthesizing platinum group free catalyst layers.
- Manufacturing of catalyst layers with controlled microstructure.
- Synthesizing new gas diffusion layers with improved durability and performance.
- Synthesizing porous electrodes for reversible fuel cells.
Electrification of the chemical industry offers opportunities to use carbon dioxide as a feedstock to produce molecules of industrial interest (e.g. carbon monoxide, formic acid, ethylene, alcohols) while converting the main green-house gas (i.e. negative emissions). However, major challenges remain with operating a CO2 electrolyzer for long duration at low overpotentials, which challenge the economic feasibility of the process. In this area, we work on the following projects:
- Engineering electrocatalytic interfaces for high stability and selective to certain products.
- Manufacturing gas diffusion electrodes to prevent flooding and reduce mass transport losses.
- Tailoring wettability of gas diffusion electrodes for stable operation in flow reactors.